Arista 7280QR-C36 Load Balancing Optimization for Dual Homed Systems and Networks

Arista 7280QR-C36  The Arista DCS-7280QR-C36 switch is a purpose built flexible fixed configuration 1RU system capable of supporting a wide range of interface choices. Its designed for the highest performance environments such as IP Storage, Content Delivery Networks, Data Center Interconnect and IP Peering. The 7280QR-C36 is optimized for environments with dual connected nodes such as storage and for spine applications with dual homed leaf switches. This technical application note describes the internal optimized load-balancing mechanism used within the switch and how network architects can best deploy this system to maximize overall system performance. The internal architecture of the DCS-7280QR-C36...
Continue reading →

Load Balancing with ECMP: Hardware Configuration Lookup

Abstract: This publication illustrates a technique which can be used to find exactly how Arista devices program routes to send traffic across multiple available paths. An example will be given on the Arista DCS-7150S-52-CL-R running EOS version 4.14.8M. Initial configuration: As an IGP we are using OSPF with maximum paths feature configured: Arista(config)#router ospf 1 Arista(config-router-ospf)#maximum-paths 32 There are two iBGP peers configured via a peer-group “pg1”: Arista(config)#router bgp 65001 Arista(config-router-bgp)#neighbor pg1 maximum-routes 16000 Arista(config-router-bgp)#neighbor 172.20.18.49 peer-group pg1 Arista(config-router-bgp)#neighbor 172.20.18.121 peer-group pg1 iBGP advertisements: * >   10.82.2.32/27       172.20.16.143    0       100     0       64920 64944...
Continue reading →

Fabric Visibility

A leaf and spine fabric is challenging to monitor. The fabric spreads traffic across all the switches and links in order to maximize bandwidth. Unlike traditional hierarchical network designs, where a small number of links can be monitored to provide visibility, a leaf and spine network has no special links or switches where running CLI commands or attaching a probe would provide visibility. Even if it were possible to attach probes, the effective bandwidth of a leaf and spine network can be as high as a Petabit/second, well beyond the capabilities of current generation monitoring tools. The 2 minute video...
Continue reading →